One-piece lamp socket



June 29, 1954 M. ZION 2,682,650

ONE-PIECE LAMP SOCKET Filed April 11, 1951 INVENTOR. 1%5'55 Z mm ATTOR;VE Y.

Patented June 29, 1954 ONE-PIECE LAMB SOCKET Moses Zion, Brooklyn,N."Y., assignor=-to The Lionel Corporation, New York, N. Y.,.a'corporation of New York Application April 11, 1951, Serial No;"220,404

1 Claim. l The present invention relates to one-piece lamp .sockets andis more particularly directed towards die-cast lamp sockets suitable foruse with pin type lamps wherein a spring normally holds the pins againststops in bayonet-like slots.

According to the present invention, .the entire socket structure,including the slot arrangement to accommodate the pins on the lamp, thechamber for the lamp base and the abutment for the spring is formed in asingle die casting. Such die casting elements replace the usual sheetmetal, multiple piece lamp sockets employed for this purpose.

Other and further objects will appear as the description proceeds:

The accompanying drawings show, for purposes of illustrating the presentinvention, an embodiment in which the invention may take form, togetherwith a method of manufacturing the same, it being understood that thedrawings are illustrative of the invention, rather than limiting thesame.

In these drawings:

Figure l is an exploded perspective view showing a lamp socket, lamp andassociated parts;

Figure 2 is a rear elevational View of a double lamp socket with partsin section on the line22 of Figure 3;

Figure 3 is an elevational view with parts in section on the line 3-3 ofFigure 2;

Figure 4 is a sectional view illustrating the lamp and lamp socketassembled;

Figure 5 is an enlarged perspective view illustrating the path taken bythe pin in entering the pointed slot;

Figure 6 is a view illustrating the mold parts employed in making thedie casting, the mold being open;

Figure 7 is a sectional view through the closed mold, showing thecasting in the mold;

Figures 8 and 9 are fragmentary sectional views on the lines 8-43 and9-9 of Figure 6; and

Figure 10 is a fragmentary sectional view on the line |lll0 of Figure 7.

A conventional miniature lamp is indicated at l0. Such a lamp has ametal base H, a center contact I2 and two pin contacts I3.

The drawings illustrate a double lamp socket, such as would be employedin the semaphore signal of a toy railroad system. It has two sockets,indicated generally at 2|I20 for the lamps.

Each socket is in the form of a recess in a die-cast body 2|. Thisrecess has cylindrical walls 22, 22, which occupy less than one-half thesurface of a circular cylinder. These cylindrical wall portions a-reseparated by slots having narrow front portions 23 and wide rearportions 24. One wall of each slot is straight, as indicated at 25,while the other wall is stepped, as indicated at 26a, 26b and 260. Theportion 23b forms a reverse angled step, which forms a nose at 2'! and arecess at 28.

At the bottom of the socket forming recess is a rear opening 29 andinwardly extending bottom walls 33, 30. At the front or open end of thesocket, the casting is provided with beveled surfaces 3|, 3|, whichextend to the straight sides of walls 25 of the slots. These beveledsurfaces do not, however, extend to the side wall portions 26a of theslots, as indicated at 32. The latter form stops for the lamp pins.

The external configuration of the socket will vary according to the useto which the socket is to be put. It is here shown in the form of atwo-lamp toy semaphore signal, and the casting is provided with visors32, 32, and lugs 33 adapted to receive mounting screws.

A lead wire 35, Figure l, is secured to a center contact 36 carried onan insulating washer 31, the wire passes through a coiled spring 38 andan apertured insulating washer 39 and the aperture 29 in the casting,and the parts will normally be held in place when the wire is secured toa terminal.

In use, the lamp base is passed into the socket and the pins I3 broughtagainst the beveled surfaces 3|. Turning the lamp causes the pins totravel along 3| until, as shown in Figure 5, they abut the side portions26a of the slots. The pressure on the lamp forces the pins in past thenose portions 2'! and they readily pass into the recesses 28. The springthen holds the lamp in place.

The socket is made in a die casting mold. The part 50 at the left,Figures 6 and 7, has the desiredconfiguration to form the face of thesocket, including an oblique fillet at 5!, which forms the bevel 3| andbifurcations 52--52, shown in cross section in Figure 8. These havearcuate sides 52a and straight sides 52b and a diameter equal to thediameter of the recess 22 of the socket to be produced. The sides 5217are spaced the width of the wide portions 24 of the slots.

The other mold part 53, shown at the right of Figures 6 and '7, has ablade 54 of a width to pass between the straight sides 52?) of thebifurcations 52 on the mold part 50. The major portion of this blade isthe central part of a cylinder of larger diameter than the cylinderform- 3 ing the bifurcations 52, and of the width of the wide portions24 of the slots, so as to form such wide portions. The front end of theblade 54 is cut back at the opposite corners, as indicated at 55, to beof the diameter of the bifurcations 52 for a sufiicient depth to formthe narrow side portions 26a of the slots, and is beveled, as indicatedat 56, to provide the oblique surfaces 261).

When the mold is closed, as shown in Figure 7, the cavity formed by theblade, the bifurcations and adjacent fillets is such as to form thecasting of the desired contour. The remainder of the mold is arranged togive the die casting the desired external contour, fitting it for aparticular use or mounting arrangement.

Since it is obvious that the invention may be embodied in other formsand constructions within the scope of the claim, I wish it to beunderstood that the particular form shown is but one of these forms, andvarious modifications and changes being possible, I do not otherwiselimit myself in any way with respect thereto.

What is claimed is:

A one-piece lamp socket for use with a lamp of the type havingoppositely extending pins, said socket having a body in the form of adie casting having a recess with cylindrical walls and having in saidwalls two longitudinally extending pin-receiving grooves diametricallyopposite one another, the grooves each having a straight side wall and astepped side wall making the inner portions of the grooves wider thanthe outer portions, the stepped walls including reverse angled stepsinto which the pins are movable when the lamp is inserted and turnedangularly, the body having an inwardly beveled edge about the outside ofthe recess to accept the pins and guide them into the wall slots, thefront portion of the stepped wall of each slot extending beyond thecorresponding beveled edge to form a stop.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,281,237 Weaver Oct. 8, 1918 1,387,926 Hills Aug. 16, 19211,547,722 Benjamin July 28, 1925 1,922,687 Juergens et a1 Aug. 15, 19332,221,078 Dotterer Nov. 12, 1940 2,283,934 Jorgensen May 26, 19422,320,627 Lundell June 1, 1943 2,357,311 Carlson et al. Sept. 5, 1944

